Integrated circuitry may be fabricated over and within semiconductive substrates. Individual device components of the circuitry may be separated or electrically isolated from other device components by dielectric or other isolation formed over and/or within the semiconductive substrate. One form of isolation is commonly referred to as trench isolation, wherein trenches are etched into semiconductive substrate material and subsequently filled with one or more dielectric materials.
Integrated circuitry can be fabricated to have many functions, and may include many different electronic devices such as capacitors, transistors, resistors, diodes, etc. One type of circuitry is memory circuitry comprising an array of individual memory cells. In some memory circuitry, individual memory cells include a field effect transistor and a charge storage device, for example a capacitor.
One type of electronic device is a recessed access device. These devices may include a field effect transistor where the conductive transistor gate is formed within an opening within semiconductor material. A gate dielectric separates the conductive gate from the semiconductor material, and a pair of source/drain regions is formed within the semiconductor material elevationally higher than the conductive gate material. Recessed access devices may be electrically isolated relative to other devices by an isolation gate construction that may be formed deeper within the semiconductor material than the gate construction of a recessed access device.